Adhesive tape dispenser



March 10, 1942.

A. A. ANDERSON ADHESIVE TAPE DISPENSER Filed March 15, 1939 4Sheets-Sheet l March 19, 1942. ANDERSON 2,275409 ADHESIVE TAPE DISPENSERFiled March 15, 1939 4 Sheets-Sheet 2 N max 07 ESQ M36074.

y L ,I

March 10, .1942. D N 2,275,409

ADHES IVE TAPE DISPENSER Filed March 13, 1939 l 4 Sheets-Sheet z I .5206or:

o'zzzrfafizcleniom WW1 W Z March 10, 1942. A. A. ANDERSON 2,275,409

I ADHESIVE TAPE DISPENSER Filed March 13, 1959 4 Sheets-Sheet 4 wfmPatented Mar. 10, 1942 ADHESIVE TAPE DISPENSER Arthur A. Anderson, St.Paul, Minn., assignor to Minnesota Mining & Manufacturing Company, St.Paul, Minn., a corporation of Delaware Application March 13, 1939,Serial No. 261,537

16 Claims.

This invention relates to an adhesive tape dispenser adapted to receivea roll of non-drying pressure-sensitive adhesive tape and automati callyeject predetermined unit lengths which the operator cuts off with ashear, each operation of the shear causing the next unit length to beautomatically advanced for cutting oil. The only effort required of theoperator is to push down the handle of the shear blade with the fingertips of one hand and to remove the pieces of tape as they are out off.

A feature of the dispenser is that it can be quickly adjusted to varythe predetermined unit length of tape to be dispensed. Another featureis that when a piece of tape is cut off it is automatically positionedwith its inner end portion temporarily adhering to a support or ledgefrom which it can be readily removed for use, as for example byemploying the fingers of the same hand employed in operating the shear.Other features and advantages will be apparent from the description anddrawings of an illustrative portable embodiment.

The described embodiment illustrates a form of construction designedespecially for use in dispensing a normally tacky and pressure-sensitiveadhesive tape having a backing of unified creped paper, exemplified bythe adhesive tape of this kind which is sold under the trade-markScotch," for example. It will be understood, however, that the inventionis notlimited to a device for dispensing any one particular kind ofadhesive tape, since the principles involved may be employed whereverexpedient; and the illustrated form may be modified, if necessary ordesirable, to adapt it to other forms of adhesive tape, includinggumrned paper tape. By normally tacky and pressure-sensitive adhesivetape, reference is made to the property of the adhesive coating beingstably in a condition such that it does not need to be activated by heator solvents, or be otherwise prepared, in order to secure good adherenceto surfaces against which the adhesive surface is pressed by a lightapplication of manual or mechanical pressure. Modern tapes of this typehave a non-offsetting adhesive, the adhesive being more cohesive thanadhesive, so that the tape can be unwound from rolls and removed fromsurfaces to which temporarily applied without adhesive transferoccurring.

In the accompanying drawings:

Fig. 1 is a side elevation view of the side carrying the tape dispensingmechanism proper;

Fig. 2 is a plan view;

Fig. 3 is a front elevation view as the operator faces the dispenser;

Fig. 4 is a side elevation showing the opposite side where the cam shaftand its variable ratio drive are located for regulating the length ofthe tape to be dispensed;

Fig. 5 is a longitudinal vertical section through the axes of thedispensing rollers and the driving shaft, taken on 5--5 of Fig. 2;

Fig. 6 is a transverse vertical section through the tape dispensingmechanism, taken on 6-6 of Fig. 2; and

Fig. 7 is a simplified circuit diagram, showing the operation of theelectric control system.

The dispensing machine proper is located upon the rectangular top IU ofa box H, the latter having an open bottom and being screwed to base l2.The switching elements and wiring of the motor control system arelocated within the box and are not shown, although indicatedschematically in the circuit diagram, since the construction thereof isnot part of the invention and suitable devices can be readily found onthe market. The top of the box thus serves as the base for themechanical elements of the mechanism, and also for the electric drivingmotor. Looking toward the front of the machine, the right-hand half ofthe top base supports the tape dispensing unit, and the left-hand halfsupports the driving unit, including the motor, the cam shaft and thevariable ratio drive.

The dispenser mechanism will be described first. Extending along thefront of the top base and secured thereto, there is a rectangularupright supporting plate l3, which is recessed along the front to carrya fixed shear blade M, the upper edge of which is adjacent the upperedge of the supporting plate. A stiff metal strip l5, having the upperpart bent forward at right angles to provide a fiat horizontal tapesupporting ledge it, rests against the outer face of the shear blade,the ledge being spaceda short distance below and parallel to the edge ofthe blade. The ledge strip and the blade are jointly secured to thesupporting plate by machine screws l1 and I8 Joumaled in the outer endportions of the supporting plate and blade, and in support I9 located atthe rear right corner of the top base, is shear shaft 20, which runsback at right angles to the fixed blade. The front end of this shaftprojects through the fixed blade and is secured to the end of moveableshear blade 2|, which pivots with the shaft to coact with the fixedshear blade in cutting off tape. The angle be- .for manually pushingdown the blade with the fingers of one hand. The blades are preferablyof the right-angle edge type, as shown. The

moveable blade and the tape supporting ledge are located such that whenthe moveable blade has been pushed down past the resisting or cuttingedge of the fixed shear blade, it will bear against the top surface ofthe ledge. The shear shaft is provided with a stop finger 23, which isshaped to bear down against the top base when the moveable shear bladeis in normal open position and thus limit the upward travel of saidblade, so that the blade angle is in the neighborhood of 45. Themoveable blade is triangularly shaped so that the handle will be at onlya small angle to the horizontal when the blade is in open rest position,thus making it very convenient to operatewith the fingers.

The shear shaft extends rearwardly of support 19 and is provided with anadjustable collar 24 spaced from said support, and which can be lockedin desired position by means of its setscrew, and about the shaftbetween these there is located a concentric loaded coil spring 25, theends of which are fastened to the support and collar. The spring isloaded by twisting and compression so as to subject the shear shaft bothto torque and to rearward pushing, each of which can be varied byadjusting the position of the collar relative to the shaft. One functionof the spring is to maintain the moveable shear blade in normally openposition, except when it is being operated, and to return it toopen-position when released by the operator at the end of a cuttingstroke. A second function is to cause the cutting edge of the moveableblade tobear firmly but yieldably against the coacting cutting edge ofthe fixed blade during the cutting stroke as the contact point betweenthe two moves across the tape. The shaft, at a point intermediate to itssupports, carries an eccentric or cam 26 secured thereto by set-screws21 and 28. This cam coacts with an underlying switch actuating pin 29(see Fig. 1), which projects vertically through the top base, and isarranged so that the pin will be held in pushed down position at alltimes except when the moveable shear blade is in or near closedposition, at which time the cam permits the pin to be in raisedposition. The pin actuates a shear-controlled switching device (notshown, although symbolically indicated in Fig. 7) located below the topbase and within the box, comprised of two single-pole one-waymicroswitches, one of which is in normally open position and the other.in normally closed position when the shear is in or near closedposition, being held closed and open, respectively, at other times.

, Thus the operator causes these switches to be actuated in closing andopening the shear.

There is a supporting block 30, parallel to and spaced back from thesupporting plate I3 and having a top surface slightly below that of theand extends forwardly with its front edge resting just behind thecutting edge of fixed shear blade l4. The\ table plate isstraight-knurled longitudinally by means of a multiplicity of smallridges and grooves extending from the rear to the front edge, i. e., inthe line of travel of tape moving forwardly above the plate to theshear. The knurling reduces adhesion of the adhesive tape to the tableand minimizes sticking of the tape as it moves along. The front endportion of the table plate is slightly arched or humped, see 34, andjust behind this portion the plate is slotted out to provide a series ofspaced-apart rectangular. openings extending transversely across theplate, there being four such openings in the illustrated embodiment.

Below said openings there is a transverse driven roller shaft 35, theouter end of which is journaled in support 36 located to the'right ofthe table, having its axis parallel to the shear blade edges. The rollershaft is turned down so as to provide a series of small, short,spaced-apart, tape propelling and dispensing rollers 31, which projectupwardly through the openings in the table plate, and one of which is ateach side of the plate, thus making a total of six in the illustratedembodiment. These dispensing rollers are straightknurled longitudinallyby a multiplicity of small ridges and grooves running parallel to theaxis and hence atright angles to the knurling of the table plate. Thetop extremities of the rollers project slightly above the adjacentsurface of the table plate and serve to grip the lower, tacky,

. face of the adhesive tape 38 for propelling it along during rotationof the roller shaft.

Immediately above and parallel to the roller shaft 35, thereis normallylocated an idle roller 39, having straight knurlings extendinglongitudinally, which presses yieldably against interposed adhesive tapeand thus coacts with driven propelling rollers 31 by pressing the tapeinto positive operative engagement with the latter (see Fig. 5). An axle40 passes through the bore of the idle roller and is journaled in theends of the arms of the two supporting bell cranks 4| and 42, which arefulcrumed on the ends of spindle 43 which passes through supportingblock 30, the other arm ends being fastened to loaded coil springs 44and 45 which are attached to the rear part of the top base by screws 46and 41. These springs thus function through the bell cranks to yieldablypress the idle roller down, but the latter can be swung back when tapeis to be threaded between the rollers. If desired, means can be providedfor adjusting the tension of the springs so as to vary the pressureexerted by the idle roller to best accommodate various types of tape.

A box-like oil reservoir can 48 is located below the dispensing rollers31 and against the rear of upright plate 13 (see Fig. 6), having alength somewhat greater than the width of the overlying table plate 3|.A wick 49, of suitable material such as cloth or felt, in the form of atape or sheet having a width approximating that of the table plate,extends from the reservoir, passing through duct 50, which runs upwardlyfrom the front and top of the oil reservoir can to just below the top ofthe upright plate, and the wick passes forwardly between thetable plateand the tops of the underlying upright plate and fixed shear blade toterminate with its edge directly above, and in alignment with, thecutting edge of the shear blade. When tape is cut, the operation isfacilitated by the lubricating action of this wick, as hereafterexplained in more detail. The oil reservoir can has a hole 5| in its topthrough which oil can be squirted for replenishment.

At the rear of the top base there is located a metal yoke 52, secured tothe rear wall of the box, having arms extending rearwardly and upwardly'therefrom. This yoke serves as the support .and holder for the roll ofadhesive tape being dispensed. The ends of the yoke arms are slotted toreceive the projecting hubs 53 and 54 of a wheel 55 upon the rim ofwhich the core of the roll of adhesive tape 38 has been slipped. Theyoke is so positioned and constructed that the adhesive tape roll is inalignment with the dispensing rollers and shear and the axis of the taperoll is about level with the top of the.

table plate. The roll of tape is inserted so that the tape will have theadhesive side down as it is drawn forward, and is located so that thetape normally Just clears, or rests lightly against, the top of thetable plate as it is drawn from its roll by rotation of the dispensingrollers (see Figs. 1 and 2).

Referring now to the left hand side of the machine, which includes thedriving unit and motor, the right end of driving shaft 60 fits into theleft end of driven roller shaft 35 and is secured by set-screw 6| Themiddle of the driving shaft carries a worm wheel 62 which engages worm63 on shaft 64 of a small electric motor 65, whereby speed reductionoccurs (see Fig. This worm drive is contained in housing 86, whichprovides supporting journals for the driving shaft, and which isfastened to the front of the motor. The electric motor is of theuniversal type, adapted to operate on both alternat- I ing and directcurrent, and is mounted on the top base to the rear of the worm wheel sothat its shaft lies above and crosses at right angles to the saiddriving shaft. The left end of driving shaft 60 extends beyond thehousing and is threaded to receiv a friction wheel 61 having a rubberrim 68, the position of the wheel being adjustable since it can bescrewed back and forth for some distance. A winged lock nut 69 is alsocarried by the driving shaft and can be screwed against the outer sideof the friction wheel to lock it in the desired position.

, A driven cam shaft 10 runs to the rear, its axis approximatelyintersecting the left end of the driving shaft, at right angles, andcarries on its front end a disk II which can be positioned to bearagainst the rubber rim of friction wheel 61. Thus by moving the frictionwheel back and forth on the driving shaft, the turning ratio between thetWo shafts can be varied over a substantial range so that a variableratio friction drive for driven cam shaft 10 is provided. The cam shaftis journaled in upright 12, located behind the disk, and in upright 13,located toward the rear of the top base. The rear end of the cam shaftterminates within upright 13. A screw 14 is threaded in from the rear ofup right 13 and the two facing ends (of shaft '10 and screw 16) arecupped out and a bearing ball i5 is located therebetween. Screw It has aknurled head it and carries a knurled lock nut 11 to bear against therear of upright 13, permitting ready adjustment. This screw permits offorcing driven shaft it! forward so that disk 1i will bear firmlyagainst the friction wheel, and permits retraction of the disk when itis desired to adjust the position of the friction wheel.

Driven shaftil) carries an eccentric or cam 18, located between the twoJournals, and which turns with the shaft to force down underlyingvertical pin 19 just before the completion oi one turn. At the start ofa cycle of operation of the dispenser, the pin is up and spaced from thecamming surface. As the cam shaft turns, the camming surface remainsclear of the pin .until Just before the end of the turn, and thendepresses the pin for an instant before stopping,

box and serves for plugging in the machine to Cord any convenientelectric outlet or socket. 82 connects to the rear of the motor andpasses down into the box through a hole in the top for connection to themotor control system.

M ode of operation A roll of tape is placed in its holder, and the endis pulled toward the front oil/the machine and threaded between therollers, the tacky adhesive side being underneath so as to contact thetape propelling rollers which project slightly above the corrugatedtable plate 3!. Different widths of tape can be used, since there are anumber of such propelling rollers. As previously mentioned, the axis ofthe tape roll is located so that the tape as it approaches the rollerswill just ,clear, or press only lightly against, the knurled tableplate. This plate guides the tape so that it will be ejected from therollers toward the shear. The humped or arched portion 34 at the frontend of the plate prevents the ejected tape from pressing, or beingpressed during the shearing step, against the table plate portionsituated to the rear thereof and in front of the rollers. Thus there isa minimum of opportunity for the advancing tape to stick to the tableplate, and the knurled surface of the latter further reduces frictionaland stictional engagement of the tape.

The operator turns on the current by flipping toggle switch Bil,assuming that the dispenser has been plugged in, and is ready to begin.

He places the finger tips of one hand in the trough of the finger handle22 of the movable shear blade 2i and presses downward with a quickmovement, causing the shear to close, the projecting tape being cut offas the moving blade passes the resisting edge of fixed shear blade 14,The inner end of the severed piece of tape is carried down by the undersurface of the moving shear blade and is pressed against the top of theunderlying ledge H5 at the end of the stroke (see Fig. 4). The tackyadhesive adheres to the ledge and the piece of severed tape istemporarily held in position for convenient removal. During the cuttingor shearing operation, the tape is pressed against the underlying end ofoil wick 49 in advance of the angularly descending moving shear blade,thus squeezing out a small amount of oil upon the cutting edge portionand front face of the fixed blade, and upon the adhesive surfaceadjacent the cutting edge. The presence of this oil makes for an easy,clean cutting of the tape, including the adhesive coating thereof; andit prevents the adhesive from sticking to the shear blades, thusfacilitating the pushing down of the inner end portion of the severedtape to the ledge,

fouled with adhesive material.

At the end of the down stroke of the moveable shear blade, the operatorlifts his hand and the blade snaps back to normally open position. Thissame hand may then be used to grasp the dispensed piece of tape andremove it from its temporary support ready for application to a packageor other article to be sealed or labelled, for example. J

As the moving shear blade starts to rise, the motor circuit isautomatically closed and by the time the blade is out of the way thenext unit length of tape will have started to move forward between theshear blades, being propelled by the dispensing rollers 31, which aredriven by the motor as previously indicated. This will continue untilcam shaft 10, driven by the motor through driving shaft 60 (which alsodrives the dispensing rollers) and the variable ratio friction drive,has made substantially one turn, whereupon the motor stops, leaving thepredetermined unit length of tape projecting in posi tion for-cuttingoff. The desired length can be fixed in advance, as previouslymentioned, by adjusting the position of friction wheel 61 (on thedriving shaft) relative to the center of disk I! (on the cam shaft) soas to regulate the extent of rotation of the driven tape propellingrollers per turn of the cam shaft. The operation of the motor controlsystem will be described hereinafter.

As previously mentioned, the basic machine can be readily modifiedas maybe desired for use in connection with various kinds of adhesive tape. Ifa type of tacky, pressure-sensitive adhesive tape is employed whichrequires a relatively strong force to pull it from its roll, beyond thecapacity of the dispensing roller device specifically illustrated,obviously an auxiliary pull drum can be interposed to be driven by themotor in suitable timed relation. Or the rollers can be increased insize, or a single roller used, arranged to afford a greater surface areato grip the adhesiv'e surface of the tape. If it is desired to dispensea non-tacky tape, such as the gummed paper form, the propelling rollers,or the coacting idle roller 39, or both, can be provided with rubber orother suitable surfaces to give increased traction if found necessary;and suitable guide means can be provided to properly direct the tape tothe rollers. Since such gummed tape is non-tacky, the supporting ledgel6 can be modified so as to releasably hold the end of the severed tape.For example, a support having a row of prongs or teeth can be used, theunder side of the moveable shear blade being recessed so that the bladewill press the inner end portion of the tape into gripping engagementtherewith. A moistening sponge device can be located to provide a fiatmoistening surface extending forwardly of the temporary tape support,the operator pressing the severed piece of tape down against it and thenpulling the tape up and off for sealing application.

Control system The circuit diagram of the electric control system is setout schematically in Fig. 7, and as the connections will be readilyapparent upon inspection they will not be detailed, although indicatedin the following description of mode of operation. The system works oneither alternating or direct current.

When moveable shear blade 2| is in open position, the cam 26 on theshear blade shaft presses pin- 29 down so as to hold the normall closedsingle-pole one-way switch 90 in open position and the normally opensingle-pole one-way switch 9| in closed position. When the blade ispusheddown, and just before it reaches the end of the stroke, the campermits pin 29 to rise so that switch 90 will close and switch 9| willopen. And shortly after the blade is released and has started up. thecam again opens switch 90 and closes switch 9|. The switches are of atype which require but little motion of the actuating pin to causeopening and closing. and they are mechanically coupled' so as to beoperated simultaneously by pin 29.

A relay is provided, of the kind which will function on eitheralternating or direct current, having a field coil 92, which whenenergizedholds the two normally open single-pole one-way switch units 99and 94 in closed position.

A single-pole two-way switch is actuated by pin 19 which is depressedmomentarily Just prior to the completion of each'turn of cam 18, on thecam shaft driven by the motor 65 through the variable ratio frictiondrive, as heretofore described. The nomially closed connection isdesignated 95, and the normally open connection is designated 9G.

' and to one terminal of relay field 001192, and it will be understoodthat tliese connections remain closed at all times during the operationof the dispenser, that is, until the line switch is opened. Theconnections between the other terminals and the other side of the lineremain open at the beginning of the cycle of operation, but becomeclosed as will now be described.

When the shear blade 2| nears the end of its down stroke, it'causesswitch 90 to close, thus closing the current path through normallyclosed cam switch connection 95 to the previously disconnected terminalof the relay field coil. The latter is energized and closes relayswitches 93 and 94, and switch 93 being shunted across 90, the openingof the latter will not break the field coil circuit. Switch 9| is nowopen and prevents the motor from starting.

As the shear blade starts upward, 90 opens without effect on the relayfield coil (since 93 is now closed), and 9| closes to complete the motorcircuit through closed relay switch 94. The motor causes tape to bedispensed and turns cam 18. Just before the latter completes one turn,it operates through pin 19 to momentarily open the cam switch connection95, thereby breaking the connection to the relay field coil and causmgrelay switches 93 and 94 to open. The opening of 94' breaks the motorconnection therethrough, but the motor remains connected due to thesimultaneous closing of cam switch connection 96 (which is connectedacross 94) and thus piovides power to turn cam 18 so that it clears pin19 and allows the latter to rise. As soon as p.n I9 rises, 96 opensagain, thus breaking the motor circuit and stopping the rotation of cam18 and the rotation of the tape dispensing rollers. This completes thecycle of operation.

It may also be mentioned that since 96 is closed when relay switch 94opens (the latter being in the motor circuit when closed), arcing of 94is avoided, which is desirable since the simple type of relay which maybe used leaves the switching contacts in the open within the box H,whereas the cam switches are purchased and installed as closed units. 4

It will be understood that the foregoing description of an embodiment ofmy invention has been given for purposes of illustration and notlimitation.

What I claim is as follows:

1. In an adhesive tape dispenser, a normally open shearing means-forcutting off predetermined unit lengths of the tape, driven roller meansadapted to propel the tape forwardly from a roll thereof to and throughthe open shearing means, means, for the controlled driving of saidroller means including an electric motor, switching means actuated bythe shearing means to start the motor upon the opening of the shearingmeans following the cutting off of tape and switching means actuated bythe motor to stop the motor when the roller means has been drivensufilciently to propel a predetermined unit length of the tape inposition for cutting'off by subsequent operation of the shearing means.

2. A device according to claim 1 in which the driven roller means forpropelling the tape comprises a series of short rollers on a commondriven shaft, a yieldable parallel idle roller pressing thereagainst andcoacting with said rollers for propellin tape, and in combinationtherewith a table plate having openings through which said rollers onthe driven shaft project, said table plate extending forwardly to theshearing means.

3. A device according to claim 1 in which the driven roller means forpropelling the tape comprises a series of short rollers on a commondriven shaft, a yieldable parallel idle roller pressing thereagainst andcoacting with said rollers for propelling tapepassing therebetween, thesurface of each roller having a straight knurling extending parallel tothe axis, a table plate extending at right angles and having openingsthrough which said rollers on the driven shaft project, said table plateextending in both directions from the rollers and the forward endterminating at the shearing means and being slightly arched, the surfaceof the plate having a straight knurling running longitudinally and atright angles to the knurling of the rollers, a fixed shear blade havingits cutting edge near the forward end of said table plate, a moveableshear blade pivoted at one end of the fixed blade and spring means forholding the moveable blade in normally open position.

4. A device according to claim 1 in which the tape shearing meanscomprises a fixed shear blade over which the tape is propelled, amoveable shear blade pivoted at one end of the fixed blade, a handle onthe moveable shear blade, a cam shaft rotated by the moveable blade andadapted to actuate switching means for starting the motor, and springmeans for holding the moveable blade in normally open position.

5. A device according to claim 1 in which the tape shearing meanscomprises a fixed shear blade over which the tape is propelled, amoveable shear blade arranged to coact by pivoting past the fixed blade,and means for supplying oil to the cutting edge of the fixed blade andthe overlying surface of the tape as the moveable shear blade cuts thetape.

6. A device according to claim 1 in which the tape shearing meanscomprises a, fixed shear blade over which the tape is propelled, amoveable shear blade arranged to coact by pivoting past the fixed bladeand having a leading edge adapted to push the inner end portion of thesevered piece of tape past the fixed blade, and holding means adapted toreceive and releasably hold said inner end portion of the severed tape.

7. A device according to claim 1 having a fixed shear blade over whichthe tape is propelled, the outer side of ,the blade extending verticallydownwards. from the cutting edge, an oil reservoir located to the rearof the blade and a fiat oilsupplying wick extending therefrom over thetop of the blade and terminating at the cutting edge, a plate overlyingthe wick and having its forward edge just to the rear of the cuttingedge so as to expose only the edge portion of the wick and support tapeapproaching the fixed shearing blade, a moveable shear blade arranged tocut tape by pivoting past the fixed blade and spring means for holdingthe moveable blade in normally open position above the fixed blade, aledge located below the cutting edge of the fixed blade and on the outerside thereof adapted to receive and releasably hold the inner endportion of the severed piece of tape, the movable blade being arrangedto push the inner end portion of the severed tape down from the cuttingedge of the fixed blade and into engagement with the ledge.

8. A device according to claim 1 in which the controlled driving meansincludes a variable ratio drive and cam driven by the motor, said camactuating switching means for stopping the motor, permitting adjustmentof the rate of rotation of said cam relative to the rate of rotation ofthe driven roller means for propelling the tape and thus permittingpredetermined adjustment of the unit length of tape to be dispensed.

9. A dispenser adapted to dispense predetermined unit lengths ofnormally tacky and pressure-sensitive adhesive tape from a roll thereof,comprising a base, a motor, a fixed shear blade having a horizontalcutting edge and a vertical front face located at the front of the base,a ledge located on the front face below the cutting edge, a moveableshear blade pivoted at one end of the fixed blade and located to swingdown past the cutting edge of the fixed blade and meet the ledge, afinger handle on the moveable shear blade, spring means adapted to holdthe shear in normally open position, a cam connected to the moveableshear blade to turn therewith and assoelated switching means arranged toautomatically turn on the motor after the moveable shear blade completesa tape cutting operation, driven roller means located behind the fixedshear blade and adapted to propel adhesive tape to and over said bladewith the adhesive side down, a holder for a roll of tape located behindsaid roller means to supply tape thereto, an oil wick overlying the topof the fixed shear blade and terminating at the cutting edge and an oilreservoir behind the blade into which the wick runs, a table plateextending rearwardly from said cutting edge and lying above the wick toguide tape from the driven roller means to the shear blade, drivingmeans connected between said driven roller means and the motor toactuate the roller means so that tape will be propelled when the motoris running, a cam and associated switching means arranged to turn offthe motor when the cam has been driven one turn, and driving meansconnecting the cam to the motor and adjustable to vary the speed ofrotation of the cam in relation to the speed of rotation of the rollermeans used for propelling the tape whereby the predetermined unit lengthof tape dispensed can be varied.

10. In a dispenser adapted to dispense predetermined unit'lengths ofnormally tacky and pressure-sensitive adhesive tape from a roll thereof,a fixed shear blade and a coacting moveable shear blade, means forholding'the moveable blade in normally open' position, means for latteris pushed into engagement by the move- I able shear blade, the majorportion of the severed tape projecting free from support in position tobe grasped between the fingers for removal of the severed tape whendesired.

11. In a, dispenser for normally tacky and pressure-sensitive adhesivetape, shearing means comprising a fixed shear-blade and a coactingmoveable shear blade, spring means for holding the moveable blade innormally open position, an oil wick running from the rear of the fixedblade and terminating at the cutting edge thereof for lubricating theedge when tape is being cut, andcovering means overlying the wick andexposing only the edge portion at thecutting edge.

12. In a dispenser for normally tacky and pressure-sensitive adhesivetape, shearing means comprising a fixed shear blade and a coastingmoveable shear blade, spring means for holding the moveable blade innormally open position, an oil wick running from the rear of the fixedblade is automatically followed by the advancement of a unit length oftape in position for cutting off upon subsequent operation of the shearsso that successive manual operations of the shearing means results inthe cutting off of a series of predetermined unit lengths of theadhesive tape as desired.

14. In an adhesive tape dispenser, shearing means including a movableelement, tape drivin means adapted to propel the tape forwardly from aroll thereof to and through the shearing means,

and control means including means actuated by said movable element toautomatically initiate operation of the tape'driving means followingtape severing and also including means to auto- ;matically terminatemovement of the tape when a predetermined unit length is positionedforsevering, so that each severing operation is autoa means toautomatically terminate movement of and terminating at the cutting edgethereof for lubricating the edge when tape is being cut, covering meansoverlying the wick and exposing only the edge portion at the cuttingedge, and a ledge located below the cutting edge of the fixed blade andadapted to receive and releasably hold the inner end portion of severedtape when the latter is pushed into engagement by the moveable shearblade.

13. In an adhesive tape dispenser, a normally open shearing meansadapted for manual operation to cut off predetermined unit lengths ofthe tape, tape driving means adapted to propel the tape forwardly from aroll thereof to and through the open shearing means, and control meansincluding means actuated by the shearing means to initiate operation ofthe tape driving means following tape severing and also including meanstoautomatically terminate movement of the tape when the predeterminedunit length is positioned for cutting off, so that each severingoperation matically followed by theadvance of a unit length of tape intoposition for severing.

, 1 5. In combination in a otor operated dispenser for normally tacky prure-sensitive adhesive tape, driving means for advancing tape from aroll thereof, tape severing means located to permit advanced tape to becut off and including a movable element which moves when tape issevered, and control means including means actuated by said movableelement to automatically initiate operation of the'tape-advancing meansfollowing tape severing and also including the tape when a predeterminedunit length is positioned for severing, so that the severing of tape isautomatically followed by the advance of a further predetermined lengthof tape into position for severing.

16. In combination in amotor operated dispenser for normally iypressure-sensitive adhesive tape, driving eans for advancing tape from arolithereof into position for severing a predetermined unit length, tapesevering means located to permit advanced tape to be severed. andcontrol means including means responsiveto the severing operationadapted to automatically cause operation of the tape-advancing meansfollowing tape severing and also including means to automaticallyterminate movement of the tape when a predetermined unit length ispositioned for severing, so that the severing of tape is automaticallyfollowed by the advance of a further predetermined length of tape intoposition for severing.

